Low-Energy Transfer Orbit

Author: CislunarSpace

Website: https://cislunarspace.cn

Definition

A low-energy transfer orbit is a transfer trajectory designed using the dynamics of the three-body problem, offering significantly reduced energy requirements compared to conventional two-body transfers. These trajectories are primarily achieved through two approaches: invariant manifold-based transfers and weak stability boundary (WSB) ballistic transfers.

Invariant manifold transfers leverage the stable and unstable manifolds associated with periodic orbits around libration points. A spacecraft placed on the stable manifold of a target Halo orbit will naturally coast to that orbit without requiring an orbit insertion burn. Similarly, unstable manifolds provide natural departure trajectories. WSB transfers use solar gravitational perturbation to naturally capture a spacecraft into the lunar sphere of influence without a braking maneuver.

Compared to direct Hohmann-type transfers, low-energy transfers require significantly less propellant but involve longer transfer times. The tradeoff between Δv savings and mission duration must be carefully evaluated for each mission.

Key Properties

  • Two main approaches: Invariant manifold transfers and WSB ballistic transfers
  • Propellant savings: Can reduce Δv by 15-50% compared to direct transfers
  • Longer duration: Transfer times are typically much longer than conventional approaches
  • Three-body dynamics: Trajectories exploit the gravitational interplay of three bodies rather than patched two-body approximations

References

  • Koon, W. S., Lo, M. W., Marsden, J. E., & Ross, S. D. (2000). "Heteroclinic Connections Between Periodic Orbits and Resonance Transitions in Celestial Mechanics." Chaos.